package com.app.vaidyaa.client;

import com.app.vaidyaa.shared.FieldVerifier;
import com.google.gwt.core.client.EntryPoint;
import com.google.gwt.core.client.GWT;
import com.google.gwt.event.dom.client.ClickEvent;
import com.google.gwt.event.dom.client.ClickHandler;
import com.google.gwt.event.dom.client.KeyCodes;
import com.google.gwt.event.dom.client.KeyUpEvent;
import com.google.gwt.event.dom.client.KeyUpHandler;
import com.google.gwt.user.client.rpc.AsyncCallback;
import com.google.gwt.user.client.ui.Button;
import com.google.gwt.user.client.ui.DialogBox;
import com.google.gwt.user.client.ui.HTML;
import com.google.gwt.user.client.ui.Label;
import com.google.gwt.user.client.ui.RootPanel;
import com.google.gwt.user.client.ui.TextBox;
import com.google.gwt.user.client.ui.VerticalPanel;

/**
 * Entry point classes define <code>onModuleLoad()</code>.
 */
public class Myfirstapp implements EntryPoint {
        /**
         * The message displayed to the user when the server cannot be reached or
         * returns an error.
         */
        private static final String SERVER_ERROR = "An error occurred while "
                        + "attempting to contact the server. Please check your network "
                        + "connection and try again.";

        /**
         * Create a remote service proxy to talk to the server-side Greeting service.
         */
        private final GreetingServiceAsync greetingService = GWT
                        .create(GreetingService.class);

        /**
         * This is the entry point method.
         */
        public void onModuleLoad() {
                final Button sendButton = new Button("Send");
                final TextBox nameField = new TextBox();
                nameField.setText("GWT User");
                final Label errorLabel = new Label();

                // We can add style names to widgets
                sendButton.addStyleName("sendButton");

                // Add the nameField and sendButton to the RootPanel
                // Use RootPanel.get() to get the entire body element
                RootPanel.get("nameFieldContainer").add(nameField);
                RootPanel.get("sendButtonContainer").add(sendButton);
                RootPanel.get("errorLabelContainer").add(errorLabel);

                // Focus the cursor on the name field when the app loads
                nameField.setFocus(true);
                nameField.selectAll();

                // Create the popup dialog box
                final DialogBox dialogBox = new DialogBox();
                dialogBox.setText("Remote Procedure Call");
                dialogBox.setAnimationEnabled(true);
                final Button closeButton = new Button("Close");
                // We can set the id of a widget by accessing its Element
                closeButton.getElement().setId("closeButton");
                final Label textToServerLabel = new Label();
                final HTML serverResponseLabel = new HTML();
                VerticalPanel dialogVPanel = new VerticalPanel();
                dialogVPanel.addStyleName("dialogVPanel");
                dialogVPanel.add(new HTML("<b>Sending name to the server:</b>"));
                dialogVPanel.add(textToServerLabel);
                dialogVPanel.add(new HTML("<br><b>Server replies:</b>"));
                dialogVPanel.add(serverResponseLabel);
                dialogVPanel.setHorizontalAlignment(VerticalPanel.ALIGN_RIGHT);
                dialogVPanel.add(closeButton);
                dialogBox.setWidget(dialogVPanel);

                // Add a handler to close the DialogBox
                closeButton.addClickHandler(new ClickHandler() {
                        public void onClick(ClickEvent event) {
                                dialogBox.hide();
                                sendButton.setEnabled(true);
                                sendButton.setFocus(true);
                        }
                });

                // Create a handler for the sendButton and nameField
                class MyHandler implements ClickHandler, KeyUpHandler {
                        /**
                         * Fired when the user clicks on the sendButton.
                         */
                        public void onClick(ClickEvent event) {
                                sendNameToServer();
                        }

                        /**
                         * Fired when the user types in the nameField.
                         */
                        public void onKeyUp(KeyUpEvent event) {
                                if (event.getNativeKeyCode() == KeyCodes.KEY_ENTER) {
                                        sendNameToServer();
                                }
                        }

                        /**
                         * Send the name from the nameField to the server and wait for a response.
                         */
                        private void sendNameToServer() {
                                // First, we validate the input.
                                errorLabel.setText("");
                                String textToServer = nameField.getText();
                                if (!FieldVerifier.isValidName(textToServer)) {
                                        errorLabel.setText("Please enter at least four characters");
                                        return;
                                }

                                // Then, we send the input to the server.
                                sendButton.setEnabled(false);
                                textToServerLabel.setText(textToServer);
                                serverResponseLabel.setText("");
                                greetingService.greetServer(textToServer,
                                                new AsyncCallback<String>() {
                                                        public void onFailure(
                                                                        Throwable caught) {
                                                                // Show the RPC error message to the user
                                                                dialogBox.setText("Remote Procedure Call - Failure");
                                                                serverResponseLabel
                                                                                .addStyleName("serverResponseLabelError");
                                                                serverResponseLabel
                                                                                .setHTML(SERVER_ERROR);
                                                                dialogBox.center();
                                                                closeButton.setFocus(true);
                                                        }

                                                        public void onSuccess(
                                                                        String result) {
                                                                dialogBox.setText("Remote Procedure Call");
                                                                serverResponseLabel
                                                                                .removeStyleName("serverResponseLabelError");
                                                                serverResponseLabel
                                                                                .setHTML(result);
                                                                dialogBox.center();
                                                                closeButton.setFocus(true);
                                                        }
                                                });
                        }
                }

                // Add a handler to send the name to the server
                MyHandler handler = new MyHandler();
                sendButton.addClickHandler(handler);
                nameField.addKeyUpHandler(handler);
        }
}
